A review of optimum parameter values of a passive solar still and a design for southern Bangladesh

Pure and fresh water is being scarce day by day. Although Bangladesh is a riverine country, pure drinking potable water is not a cheap commodity. Most of the people in the cities boil water to drink, and people of the villages take tube-well’s water directly, which might have high amount of heavy metal like arsenic. Solar still is a cheap and very useful renewable technology, which can be used in Bangladesh extensively everywhere at the rooftop as a pure water source. Objective of this paper was to find a low cost portable and easily maintainable passive solar still for southern part of Bangladesh. All the parameters of passive solar still are studied, and it is found that an inclined stepped solar still with passive condenser, internal and external reflectors, black cotton wick, and with optimum design values can be the desired still, which would give maximum yield. Finally, the optimum values of the parameters are used to propose a cheap design.